Add option to configure the number of gunicorn workers to spawn

Author: rolandgeider

config/prod.env

@@ -164,4 +164,10 @@ FROM_EMAIL='wger Workout Manager <[email protected]>'
 # The number of proxies in front of the application. In the default configuration
 # only nginx is. Change as approtriate if your setup differs. Also note that this
 # is only used when throttling API requests.
-NUMBER_OF_PROXIES=1
+NUMBER_OF_PROXIES=1
+
+#
+# Gunicorn
+# The number of workers to spawn. This is the number of processes that will be
+# spawned to handle requests. The recommended number of workers is (2 x $num_cores) + 1
+GUNICORN_WORKERS=3